I'm currently custom weight rigging a model and I need help with it's weight paint rigging.
I tried my best to rig the model with 3 Vertex Group limit (Or was it 2? I don't know) but here's the result:
How it looks like in Blender:
https://i.imgur.com/I7DZYCM.png
How it looks like in SFM:
https://i.imgur.com/RpwxVEF.png

I did edit the studiomdl.exe for the weight link cull to be set at "0.00" instead of "0.05", which works fine with another custom model I made, and I did made a backup of the original "bin" before editing it.

I can provide the .blend if anyone wants to try out the model in Blender/SFM (Im using Blender 2.79b for the .blend file, I did test this with Blender 2.81 with the latest version of Source Tools and I got the same issue).

EDIT: I also tested with .dmx and .smd and still got the same issues.